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View Full Version : Can the timer be close when Tank developing?



brian steinberger
22-Oct-2006, 18:43
I've been developing my film in tanks with hangers with my clock about 2 and half feet in front of me on the table. I'm developing so that the emulsion faces me. Will the clock fog the film? Does it need to be absolutley dark when tray or tank developing?

Brian Ellis
22-Oct-2006, 22:50
Almost certainly not a problem. The phosphorus numbers on timers put out very little light. The numbers look bright because your eyes become accusomed to the dark. Between the fact that little light is produced and the inverse square law of light fall off applying to what little light there is, I very much doubt that your timer presents a problem.

Leonard Evens
23-Oct-2006, 07:12
I've used a timer with phosphorescent numbers for over 30 years and never experienced a problem.

j.e.simmons
23-Oct-2006, 10:58
I use a Gralab timer about two feet above my open trays with no problem, so I don't see why you would have one.
juan

Donald Qualls
24-Oct-2006, 19:23
I've had fogging in trays from my Gralab 300 when it was six inches from the translucent food container I was using for a tray, my process was fifteen minutes in developer, and the film was emulsion up. Since moving the timer to a high shelf where there's no direct (i.e. unreflected, unscattered) path to the film, the fogging has gone away. Two feet is 1/4 the light I had, and your process in deep tanks is most likely shorter than mine; in addition, the deep tank itself is opaque, so less of the light that is emitted reaches the emulsion.

Easy to test for fog, though -- put the floating lid for the tank on top of the hangers for one batch, and not for another, and include an unexposed film of the same type in each. If the two films differ in density enough to bother you, find a way to shield the tank from the timer's light.